<template>
   <div class="data_taxt">
        <button @click="count--">-</button>
        <span>{{ count }}</span>
        <button @click="count++">+</button>

   </div>
</template>

<script>
export default {
    data(){
        return{
            count : 999,
        }
    }
/*     error  `data` property in component must be a function
   data :{
    count : 100,
   }*/
} 
</script>

<style scoped>
    .data_taxt{
        margin: 20px;
    }
</style>